Changes in Goodwill (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Goodwill [Roll Forward]
Goodwill	$ 1,583,564	$ 1,586,482
Accumulated impairment losses	(329,741)	(329,741)
Subtotal	1,253,823	1,256,741
Purchase price allocation adjustments	371	(726)
Disposition	(1,129)	0
Goodwill	1,582,806	1,585,756
Accumulated impairment losses	(329,741)	(329,741)
Total	$ 1,253,065	$ 1,256,015
Percentage of fair value of Reporting Unit 1 exceeded its carrying value	10.00%		30.00%
Amount of fair value of Reporting Unit I	$ 1,900,000		$ 2,500,000

Reporting Unit, Amount of Fair Value

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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-Publisher FASB

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-Section 45

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- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a,h)

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

+ References

No definition available.

+ Details

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